Enhanced Dual-frequency Pattern Scheme Based on Spatial-temporal Fringes Method

TL;DR

This paper introduces a novel dual-frequency pattern scheme based on spatial-temporal fringes that improves phase retrieval accuracy by effectively separating low frequency lobes, reducing noise sensitivity in phase-shifting algorithms.

Contribution

The paper proposes a new dual-frequency pattern method using spatial-temporal fringes to enhance phase separation and accuracy compared to existing Fourier transform profilometry approaches.

Findings

High precision in phase retrieval demonstrated through simulations.

Effective separation of low frequency lobes improves noise robustness.

Method outperforms previous techniques in accuracy.

Abstract

One of the major challenges of employing a dual-frequency phase-shifting algorithm for phase retrieval is its sensitivity to noise. Yun et. al [H Yun, B Li, S Zhang. 2017] proposed a dual-frequency method based on the Fourier transform profilometry (FTP), yet the low frequency lobes are close to each other for accurate band-pass filtering. In light of this problem, a novel dual-frequency pattern based on the spatial-temporal fringes (STF) method is developed in this paper. Three fringe patterns with two different frequency are required. The low frequency phase is obtained from two low frequency fringe patterns by the STF method, so the signal lobes can be extracted accurately as they are far away from each other. The high frequency phase is retrieved from another fringe pattern without the impact of the DC component. Simulations and experiments are conducted to demonstrate the excellent precision of the proposed method.